In a food processor, combine the walnuts, garlic, jalapeno, grated cheese, salt, and pepper.,Process until the mixture is smooth.,Add the spinach and arugula and process until blended.,With the machine running, gradually add the olive oil.,Bring a large pot of salted water to a boil over high heat.,Add the pasta and cook, stirring occasionally, until tender but still firm to the bite, 8 to 10 minutes.,Drain the pasta, reserving about 1 cup of the pasta water.,______,Toss well.,If needed, thin out the sauce with a little pasta water and season with salt and pepper.,Garnish with the Asiago cheese shavings and serve.,If you prefer a milder pesto, remove the seeds from the jalapeno pepper before you chop it.